I remember, aged five, being given a copy of The Hobbit. I knew I wasn’t old enough yet to read it myself, so I put it carefully to one side until I was, and when I did, I wasn’t sorry.

It was a perfect combination of cosiness and danger, and there was something neatly rounded about Bilbo Baggins’s circular journey from his comfortable, well-stocked hobbit-hole in Bag End to a world of treacherous, nerve-shredding sorcery, and back again.

Neat, however, is not a word to apply to Peter Jackson’s take on J.R.R. Tolkien’s book, which has now been split up into three sprawling films. The Hobbit: An Unexpected Journey begins not with the austerely promising words “In a hole in the ground there lived a hobbit”, but with a tangled and grandiose CGI evocation of the fall of the Dwarf kingdom of Erebor. And thence to the musings of an older, nostalgic Bilbo (Ian Holm), in advance of entering the house of young Bilbo (Martin Freeman), where Tolkien himself begins.

Before Bilbo has even put one speculative, hairy foot out of Bag End, then, the cinema audience has already waded thigh-deep through blood, treasure and several intervening decades. Why not let Tolkien’s tale unfurl in its own time?

Jackson’s clock, however, is different and more erratic: although rushing to jump back and forth, it can also move at an achingly slow pace (the initial meeting of the riotous dwarves at Bilbo’s house, artfully arranged by Gandalf [Ian McKellen], seems to last forever).

Still, the director retains his undeniable feel for the power of cinema. A group of slavering trolls fancy dwarf for supper, but end up frozen in stone; the disturbing Gollum (Andy Serkis) scrabbles damply for his “preciouses”; and a forest wizard named Radagast (Sylvester McCoy) goes on a hare-brained ride on a makeshift sledge pulled by speeding rabbits.

Overall, Jackson prefers great, clanging set-pieces over nuances, which is why he’s lucky to have Freeman, an actor who plays Bilbo with a sincere expression of puzzled honesty and the suggestion of a stout, simple heart. He humanises (or hobbit-ises) the whole film.

Nonetheless, by the end of nearly three hours, we’ve only got within sniffing distance of the dragon Smaug’s lair. Whether Freeman’s talents can stretch to holding our attention through another two bloated Hobbit films remains to be seen - but Bilbo Baggins always did like to tackle the near-impossible.